Many biocidal applications have been found or suggested for organotin compounds (see J. S. Thayer, J. Organometal. Chem., 76:265 (1974); Organotin Compounds: New Chemistry and Applications, J. J. Zuckerman, Ed., American Chemical Society, Washington, D.C., (1976)). Specific organotin compounds currently used in agriculture have been reviewed (see B. Sugavanam, Tin Its Uses, 126:4 (1980); F. E. Smith, ibid., 126:6 (1980); S. Haynes, ibid, 127:12(1981)). Their use in agriculture as fungicides and pesticides is of special interest because they degrade into non-toxic inorganic compounds and therefore are not hazardous to the environment (see K. D. Freitag and R. Bock, Pestic. Sci., 5:731 (1974); R. D. Barnes, A. T. Bull, and R. C. Poller, ibid., 4:305 (1973); M. E. Getzendaner and H. B. Corbin, J. Agr. Food Chem., 20:881 (1972); R. Bock and K. D. Freitag, Naturwissenschaften, 59:164 (1972); A. J. Chapman and J. W. Price, Int. Pestic. Control, 1:11 (1972)).
Recently, a series of diorganotin dihalide complexes have been shown to exhibit anti-tumor activity (see A. J. Crowe and P. J. Smith, Chem. Ind. (London), 200 (1980)). In addition, it has been reported that N-substituted N-(triphenylstannyl)cyanamides are better antifungal agents than N-substituted N'-cyano-S-(triphenylstannyl)isothioureas and N-substituted N'-cyano-O-(triphenylstannyl)isoureas (see E. J. Kupchik, M. A. Pisano, A. M. Carroll, J. R. Lumpp, and J. A. Feiccabrino, J. Pharm. Sci., 69:340 (1980)). The N-substituted N-(triphenylstannyl)cyanamides are reported to have similar activity to ethyl N-phenyl-S-(triphenylstannyl) isothiocarbamates (see E. J. Kupchik, M. A. Pisano, H. E. Hanke and W-C. R. Tseng, J. Pharm. Sci., 67:576 (1978)). Further, triethylammonium (organocyanoamino)chlorotriphenylstannates, which are the triethylammonium chloride complexes of N-substituted N-(triphenylstannyl)cyanamides, have been found to exhibit higher antifungal activity than said cyanamides (see E. J. Kupchik, M. A. Pisano, A. M. Carroll, J. R. Lumpp, and J. A. Feiccabrino, J. Pharm. Sci., 69:340 (1980)).
The antimicrobial activity of N-substituted N'-cyano-O-(triorganostannyl)isoureas and N-substituted N'-cyano-S-(triorganostannyl)isothioureas has also been reported (see E. J. Kupchik, M. A. Pisano, D. K. Parikh, and M. A. D'Amico, J. Pharm. Sci., 63:261 (1974); and E. J. Kupchik, M. A. Pisano, A. V. Raghunath, R. A. Cardon, N. Formaini and C. Alleguez, J. Pharm. Sci., 64:1259 (1975)).
Although all of the compounds mentioned above have also been shown to exhibit inhibitory activity toward Gram-positive bacteria, they do not exhibit effective inhibitory activity toward Gram-negative bacteria. In this respect, they resemble numerous other organotin compounds disclosed in A. K. Sijpesteijn, Meded. Landbouwhogesch, Opzoekingsst, Staat Gent, 24:850 (1959); A. K. Sijpesteijn, J. G. A. Luijten, and G. J. M. van der Kerk, Fungicides, An Advanced Treatise, D. C. Torgeson, Ed., Academic, New York, N.Y., Chap. 7 (1969); A. K. Sijpesteijn, F. Rijkens, J. G. A. Luijten, and L. C. Willemsens, Antonie van Leeuwenhoek, 28:346 (1962); J. G. A. Luijten, and Organotin Compounds, Vol. 3, A. K. Sawyer, Ed., Dekker, New York, N.Y., Chap. 12 (1972).
On the other hand, certain 5-nitro-2-substituted furans are known to inhibit both Gram-positive and Gram-negative bacteria, (see A. P. Dunlop and F. N. Peters, The Furans, Reinhold, New York, N.Y., p. 164 (1953); Introduction to the Nitrofurans, Vol. 1, Eaton Laboratories, New York, N.Y., (1958); and J. H. S. Foster and A. D. Russell, Inhibition and Destruction of the Microbial Cell, W. B. Hugo, Ed., Academic, New York, N.Y., Chap. 3F (1971)). However, 5-nitro-2-substituted furans do not exhibit antifungal activity. Further, some 5-nitro-2-substituted furans are not devoid of hazards, the chief of which appears to be sensitization (see A. P. Dunlp and F. N. Peters, The Furans, Reinhold, New York, N.Y., p. 165 (1953).